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A new method to investigate disorder in ice films is proposed and applied to acetylene ice. It is based on a quantitative analysis of the infrared spectrum data, which includes: the Brendel-Bormann model for the material's dielectric function; molecular vibration modes calculated by density functional theory (DFT); a monomer-dimer model for amorphous ice; and a peak-shape analysis through Levenberg-Marquardt nonlinear regression. Acetylene ice films with different degrees of disorder were investigated with the proposed method. The results provide an estimate of the degree of disorder in the films and indicate the possibility of existence of a second amorphous phase of acetylene ice grown at temperatures of about 15 K and then annealed. This phase would be similar to the high-density amorphous phase observed for water ice. The infrared data in this work is compared with those from the literature for acetylene gas, acetylene film, and acetylene aerosol. A qualitative analysis reveals differences in the degree of disorder in each system and points to a crystallinity limit for acetylene ice film; that is, the crystalline acetylene film has a higher degree of intrinsic disorder than the crystalline acetylene aerosol.

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BACKGROUND AND AIMS: In recent years, scientific interest in triglyceride-rich lipoproteins (TRL) and remnant cholesterol has increased, focusing on the evidence that these lipoproteins are a causal factor for developing atherosclerotic cardiovascular disease (ASCVD). Furthermore, a high remnant concentration (>38 mg/dL) has been associated with several non-cardiovascular risks. We aimed in this study to describe the percentile distribution of remnant cholesterol. Additionally, we evaluated the association between remnant cholesterol plasma concentration and epidemiologically relevant cardio-metabolic outcomes such as hypertension, type 2 diabetes (T2D), and ASCVD. METHODS: We analyzed data from 9,591 adults from the National Survey of Health and Nutrition (ENSANUT) 2018 with fasting blood samples and complete medical history questionnaires. We built multivariate models to evaluate the association between chronic diseases and blood remnant concentration. To compare our 2018-sub-sample against a population reference, we used the NHANES (2005-2014) publicly available datasets by ethnicity. RESULTS: Remnants were independently associated with cardiovascular risk, diabetes, hypertension, obesity, and metabolic syndrome. For all outcomes, the blood remnant concentration was a stronger predictor than LDL. At all deciles, the blood remnant concentration was higher in ENSANUT-2018. CONCLUSIONS: A remnant blood concentration above 38 mg/dL was highly prevalent among Mexicans. Remnants were significantly associated with a higher risk of diabetes, hypertension, obesity, and cardiovascular risk. This association occurred independently of other lipid markers.

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Objective: We aimed to determine the prevalence of self-reported swallowing difficulty (dysphagia) among older Colombians and to explore the factors associated with this condition. Methods: This study presents a secondary analysis of the SABE-Colombia survey, a crosssectional study of community-dwelling older adults. The dependent variable was self reported swallowing difficulty, assessed through the question: "How often do you have difficulty or discomfort swallowing?" Descriptive and bivariate analyses of the sample were performed, followed by multivariate analysis, adjusting for confounding variables. Results: The final sample included 19 004 older Colombians, whose mean age was 69 years (56% women). The overall prevalence of swallowing difficulty was 12.2%. In the multivariate analysis, significant associations were observed between swallowing difficulty and several factors, including male sex (OR 1.14, 95%CI 1.03 ­ 1.26), age > 80 years (OR 1.26, 95%CI 1.08 ­ 1.47), dependence in activities of daily living (OR 1.62, 95%CI 1.23 ­ 2.13), cognitive impairment (OR 1.49, 95%CI 1.30 ­ 1.70), depressive symptoms (OR 1.38, 95%CI 1.15 ­ 1.65), sarcopenia (OR 1.32, 95%CI 1.02 ­ 1.69), malnutrition (OR 1.35, 95%CI 1.23 ­ 1.49), and osteoarticular disease (OR 1.18, 95%CI 1.07 ­ 1.38). Conclusion: There was a high prevalence of swallowing difficulty among older community-dwelling Colombians. Our results showed a strong correlation between swallowing difficulty and risk factors such as cognitive impairment, depressive symptoms, osteoarticular disease, and dependence in activities of daily living, but not with malnutrition or sarcopenia. (AU)

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OBJECTIVE: The purpose was to analyze age-standardized trends in diabetes mortality rates (DMR) from 1998 to 2022, stratified by sex and Mexican state, and the effects attributable to age, period, and cohort by sex. STUDY DESIGN: Joinpoint regression and age-period-cohort effect analysis. METHODS: Based on the tenth revision of the International Classification of Diseases, E11, E12, E13, and E14 codes of the death certificate, a daily record of mortality was extracted from the death certificate attributable to diabetes as the main cause. From 1998 to 2022, sexes and ages (≥20 years) were used to calculate the crude mortality rates and standardized at the national and Mexican state levels. Additionally, the age-period-cohort model was used to examine age, period, and cohort effects. RESULTS: From 1998 to 2005, the age-adjusted DMR increased by 3.6% (95% confidence interval [CI]: 2.7, 4.5) for the total population, as shown by the joinpoint regression analysis at a national level; from 2017 to 2020, it increased by 7.4% (95% CI: 0.6, 14.8). The DMR with the highest increase during the study period came mainly from states in the country's southeastern region, 2.3% to 3.7% per year. The net age and period effects showed that mortality increased with advancing age and with going time, respectively; and the net cohort effect revealed that mortality increased in more recent birth cohorts, mainly in men Rate Ratio (RR) = 2.37 (95% CI: 2.29, 2.46) vs RR = 1.13 (95% CI: 1.09, 1.17). CONCLUSION: The DMR increased among older age groups. The period effect showed that mortality increased over time. Furthermore, the cohort effect showed that mortality increased in more recent birth cohorts, especially among men.

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INTRODUCTION AND AIMS: Posttransplantation diabetes mellitus (PTDM) is a serious long-term complication that has a negative impact on graft and patient survival. The purpose of the present study was to describe the incidence of PTDM in a Mexican cohort and evaluate its association with a previous family history of diabetes (FHD). METHODS: A retrospective single-center cohort study was conducted on patients undergoing liver transplantation (LT). The primary outcome was time from LT to PTDM. The diagnosis of PTDM was established using the ADA criteria. A mediation analysis that used adjusted Cox regression models and considered pretransplant prediabetes a mediator was performed, to determine the total effect and direct effect of FHD on PTDM. RESULTS: A total of 152 patients were included, with a median follow-up time of 41 months; 19.2% (n = 29) had pretransplant diabetes. During the follow-up time, 15% of patients developed PTDM (n = 23), with an incidence rate of 4.71 cases/100 person-years. PTDM was significantly higher in patients with FHD, compared with those with no FHD (8.72 cases/100 person-years vs 2.04 cases/100 person-years, respectively; p = 0.001). The adjusted hazard ratio of PTDM for FHD was 4.14 (95% CI 1.60-10.7), p = 0.005) and 3.48 (95% CI 1.35-9.01, p = 0.010), when further controlled for pretransplant prediabetes. CONCLUSION: The occurrence of PTDM was similar to that reported in most international studies. As with type 2 diabetes, family history plays an important role in the development of PTDM, even after accounting for pretransplant prediabetes. Patients with FHD should undergo a stricter metabolic program.

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BACKGROUND AND OBJECTIVES: Allogeneic stem cell transplantation (Allo-SCT) in elderly patients is a growing practice. We aimed to determine the graft-versus-host disease (GVHD) relapse-free survival (GRFS) in patients ≥65 years who underwent Allo-SCT in two countries from Latin America. PATIENTS AND METHODS: We performed a retrospective analysis of patients ≥65 years who underwent Allo-SCT in Argentina and Brazil from 2007 to 2019. RESULTS: Ninety-eight patients were evaluated, with primary diagnoses of acute myeloid leukemia and myelodysplastic syndrome; 30% of patients had a hematopoietic cell transplant-comorbidity index (HCT-CI) score ≥3 and 49% were in complete remission. Donor types included matched sibling (n = 41), matched unrelated (n = 31), and haploidentical (HID; n = 26) donors. The conditioning regimen was myeloablative in 28 patients (14 busulfan pharmacokinetically [PK]-guided) and reduced-intensity in 70 patients. The two-year non-relapse mortality (NRM) was 29%, with a higher NRM in melphalan-based compared to other conditionings (51% vs. 33%, p = 0.02). The two-year relapse rate was 24%, with a reduction in PK-guided busulfan (0% vs. 28%, p = 0.03). The two-year overall survival (OS) and GRFS was 52% and 38%, respectively, with a significant reduction in GRFS in HCT-CI ≥3 (27% vs. others 42%, p = 0.02) and donors ≥40 years (29% vs. <40 years 55%, p = 0.02). These variables remained significantly associated with GRFS after multivariate analysis. CONCLUSION: In this cohort of elderly patients from Argentina and Brazil undergoing Allo-SCT, donor age and comorbidities significantly influenced GRFS. The role of the conditioning regimen in this population deserves further investigation.

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El cáncer de mama (CM) es la primera causa de muerte por cáncer en mujeres tanto a nivel mundial como en Chile. Basados en características clínicas, histológicas y moleculares, múltiples estudios han identificado cuatro subtipos básicos de CM, los cuales están asociados a estrategias de tratamiento específicas y diferenciadas. El CM HER2-positivo representa un 15%-25% de todas las neoplasias mamarias y se caracteriza por su agresividad, recurrencia temprana y mayor tendencia a presentar compromiso del sistema nervioso central. En las últimas décadas, nuevas terapias dirigidas se han posicionado como el estándar de tratamiento y han cambiado la historia natural de esta enfermedad, transformándola en una enfermedad potencialmente curable incluso en etapas avanzadas. Esta revisión busca entregar un resumen de las bases biológicas de esta enfermedad. Por otro lado, dada la aparición de un creciente número de nuevas estrategias de manejo sistémico, nos proponemos revisar sus mecanismos de acción analizando reportes de datos clínicos publicados y la experiencia de nuestro grupo.

Breast cancer (BC) is the leading cause of cancer death for women both worldwide and in Chile. Based on clinical, histological, and molecular features, studies have identified four BC subtypes that correlate with treatment sensitivity. Human Epidermal growth factor Receptor type 2-positive (HER2+) BC represents 15%-25% of newly diagnosed breast neoplasms; HER2+ BC is characterized by its aggressive behavior, early recurrence, and higher risk of brain metastasis. In recent years, HER2-targeted therapies have become the mainstay of treatment and have redefined the natural history of this subtype, reducing relapse rates for early-stage patients and increasing survival in advanced-stage patients. Herein we review novel treatment strategies and their mechanisms of action, along with clinical and real-world data. We also provide a summary of currently available treatments for this subtype and our local experience regarding the management of this disease.

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No Abstract available.

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Pseudomonas aeruginosa is one of the most worrisome infectious bacteria due to its intrinsic and acquired resistance against several antibiotics and the recalcitrance of its infections; hence, the development of novel antimicrobials effective against multidrug-resistant P. aeruginosa is mandatory. In this work, silver nanoparticles obtained by green synthesis using a leaf extract and fungi were tested against a battery of clinical strains from cystic fibrosis, pneumonia and burnt patients, some of them with multidrug resistance. Both nanoparticles showed a potent antibacterial effect, causing severe damage to the cell wall, membrane and DNA, and inducing the production of reactive oxygen species. Moreover, the nanoparticles derived from fungi showed synergistic antibacterial effects with the antibiotics meropenem and levofloxacin for some clinical strains and both kinds of nanoparticles were nontoxic for larvae of the moth Galleria mellonella, encouraging further research for their implementation in the treatment of P. aeruginosa infections.

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BACKGROUND/PURPOSE: The use of fluoride is known to reduce the risk of dental caries. There is limited information on the relationship between Streptococcus mutans (S. mutans) and fluoride exposure. This study investigated the association between the count of S. mutans on supragingival biofilm and fluoride exposure of scholar children. MATERIALS AND METHODS: In this cross-sectional study, 56 children from 9 to 11 years of age were selected. Fluoride concentration in drinking water, urine and saliva of each participant were assessed. The count of S. mutans was estimated by calculating the DNA copy number through a quantitative real time polymerase chain reaction (qPCR) assay. Also, sociodemographic data, oral and general health information and variables related to caries risk were evaluated. A stepwise multiple linear regression was performed in all caries related predictor variables with the count of S. mutans as the dependent variable. RESULTS: The multiple linear regression analysis showed that the concentration of fluoride in saliva (ß = -3.029, p < 0.001) and urine (ß = -2.057, p = 0.017), time of last visit to the dentist (ß = 1.968, p = 0.001), plaque index (ß = 1.637, p = 0.006) and number of surfaces with codes 3-6 (D3-6MFS) of ICDAS II criteria (ß = 0.283, p = 0.076) were significantly associated with the count of S. mutans (Adjusted R square = 0.427, p < 0.001). CONCLUSION: Fluoride levels in urine and saliva were negatively associated with the count of S. mutans in supragingival biofilm. Plaque index, D3-6MFS and time of last visit to the dentist showed a positive association.

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INTRODUCTION AND AIMS: Colonoscopy quality is measured by the degree in which the examination increases the likelihood of obtaining adequate results on health. Our aim was to develop an instrument for evaluating the quality of screening colonoscopies, taking into account the performance of endoscopists and endoscopy units. MATERIALS AND METHODS: Mixed methodology was employed. The first stage (qualitative) consisted of a Medline search, from which a group of experts developed the quality score items. The second stage (quantitative) utilized a modified Delphi technique to reach consensus (3 rounds). We evaluated the psychometric properties of the instrument (reliability and construct validity) in elective screening colonoscopies (in patients ≥ 50 years of age), performed within the January-April 2017 time frame. RESULTS: A final instrument with 8 items was produced: (1) the Boston Bowel Preparation Scale score; (2) cecal intubation rate; (3) colonoscopy withdrawal time; (4) image documentation; (5) adenoma detection rate; (6) endoscopic surveillance planning; (7) perforation rate, and (8) continuous improvement programs. The instrument was evaluated in 323 colonoscopies performed by 31 endoscopists and found to be one-dimensional and reliable (Cronbach's alpha 0.76). Performance was compared between endoscopists (center 1) and an expert endoscopist from another center (center 2): Boston Bowel Preparation Scale score 8.3 vs. 7.36 (P < .001), cecal intubation rate 93.5 vs. 96%, colonoscopy withdrawal time 14.8 vs. 8.4 min (P < .001), and adenoma detection rate 34 vs. 52.2% (P < .001), respectively. CONCLUSION: The Colonoscopy Quality Score is a reliable and valid instrument for evaluating screening colonoscopy quality. Its results could be adapted to the usual endoscopic report to adjust monitorization frequency post-colonoscopy.

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Degradation of freshwater ecosystems by uncontrolled human activities is a growing concern in the tropics. In this regard, we aimed at testing an integrative framework based on the IFEQ index to assess freshwater ecosystem health of river basins impacted by intense livestock and agricultural activities, using the Muchacho River Basin (MRB) as a case study. The IFEQ combine multiple lines of evidence such as riverine hydromorphological analysis (LOE 1), physicochemical characterization using ions and pesticides (LOE 2), aquatic macroinvertebrate monitoring (LOE 3), and phytotoxicological essays with L. sativa (LOE 4). Overall, results showed an important reduction in streamflow and an elevated increase in ion concentrations along the MRB caused by deforestation and erosion linked to agricultural and livestock activities. Impacts of the high ion concentrations were evidenced in macroinvertebrate communities as pollution-tolerant families, associated with high conductivity levels, represented 92 % of the total abundance. Pollution produced by organophosphate pesticides (OPPs) was critical in the whole MRB, showing levels that exceeded 270-fold maximum threshold for malathion and 30-fold for parathion, the latter banned in Ecuador. OPPs concentrations were related to low germination percentages of Lactuca sativa in sediment phytotoxicity tests. The IEFQ index ranged from 44.4 to 25.6, indicating that freshwater ecosystem conditions were "bad" at the headwaters of the MRB and "critical" along the lowest reaches. Our results show strong evidence that intense agricultural and livestock activities generated significant impacts on the aquatic ecosystem of the MRB. This integrative approach better explains the cumulative effects of human impacts, and should be replicated in other basins with similar conditions to help decision-makers and concerned inhabitants generate adequate policies and strategies to mitigate the degradation of freshwater ecosystems.

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INTRODUCTION AND AIMS: Colonoscopy quality is measured by the degree in which the examination increases the likelihood of obtaining adequate results on health. Our aim was to develop an instrument for evaluating the quality of screening colonoscopies, taking into account the performance of endoscopists and endoscopy units. MATERIALS AND METHODS: Mixed methodology was employed. The first stage (qualitative) consisted of a Medline search, from which a group of experts developed the quality score items. The second stage (quantitative) utilized a modified Delphi technique to reach consensus (3 rounds). We evaluated the psychometric properties of the instrument (reliability and construct validity) in elective screening colonoscopies (in patients≥50 years of age), performed within the January-April 2017 time frame. RESULTS: A final instrument with 8 items was produced: 1) the Boston Bowel Preparation Scale score; 2) cecal intubation rate; 3) colonoscopy withdrawal time; 4) image documentation; 5) adenoma detection rate; 6) endoscopic surveillance planning; 7) perforation rate, and 8) continuous improvement programs. The instrument was evaluated in 323 colonoscopies performed by 31 endoscopists and found to be one-dimensional and reliable (Cronbach's alpha 0.76). Performance was compared between endoscopists (center 1) and an expert endoscopist from another center (center 2): Boston Bowel Preparation Scale score 8.3 vs. 7.36 (P<.001), cecal intubation rate 93.5 vs. 96%, colonoscopy withdrawal time 14.8 vs. 8.4min (P<.001), and adenoma detection rate 34 vs. 52.2% (P<.001), respectively. CONCLUSION: The Colonoscopy Quality Score is a reliable and valid instrument for evaluating screening colonoscopy quality. Its results could be adapted to the usual endoscopic report to adjust monitorization frequency post-colonoscopy.

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Liver transplantation is a lifesaving treatment that improves survival and quality of life. The procedure requires adequate transplant candidate selection carried out by a multidisciplinary team. Psychosocial evaluation is a necessary part of recipient selection and its primary aims are to identify problems and psychosocial needs of the patient and his/her family, to improve transplantation outcomes. Different psychosocial conditions are considered risk factors for morbidity and mortality after transplantation. The presence of those factors per se is not an absolute contraindication, thus adequate evaluation promotes equal access to healthcare, improves results, and optimizes resources. The present review provides an overview of and guidelines for the most important psychosocial issues during the pretransplantation phase.

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El realizar un tratamiento ortodóntico sólo en base a referencias de tejidos duros, puede llevar a resultados estéticos desfavorables, debido a la gran variabilidad que existe en los tejidos blandos que los recubren. Arnett et al. (1999) presentaron un análisis basado en los tejidos blandos y determinó normas que definen un rostro armónico. Sin embargo, éstas normas se obtuvieron de pacientes norteamericanos y puede que no reflejen los conceptos estéticos de nuestra población. El objetivo del presente trabajo fue determinar valores de armonía facial para la población chilena, utilizando el análisis cefalométrico de tejidos blandos presentado por Arnett et al., y compararlos con los valores previamente establecidos para la población caucásica. Se analizaron 200 fotografías y se clasificaron los perfiles en balanceados y no balanceados según el criterio de un grupo de especialistas. Posteriormente se analizaron las telerradiografías correspondientes a los perfiles clasificados, con el análisis cefalométrico de tejidos blandos. Los valores de las diferentes variables fueron analiza dos separadamente por sexo, clase esqueletal y biotipo facial, y se determinaron las diferencias entre las variables presentadas por Arnett et al. y las obtenidas en el presente estudio. Para ello se utilizaron pruebas de significancia estadística como el test t y otros no paramétricos. Sólo se encontró diferencias significativas en dos variables respecto de las normas sugeridas por Arnett et al., correspondientes a un menor espesor del labio inferior en ambos sexos, y una mayor prominencia del pómulo en mujeres chilenas, por lo que consideramos que los valores de armonía de Arnett et al., pueden ser también aplicados como parámetro estético para la población chilena.

Performing an orthodontic treatment based only on hard tissue references can lead to unfavorable aesthetic results due to the great variability that exists in soft tissues that cover them. In 1999, W.Arnett, presented an analysis based on soft tissues and determined norms that define a harmonious face. However, these standards that were obtained from North Americans and Chilean aesthetic concepts could be different. The aim of the study was to determine the values of facial harmony for the Chilean population, using the cephalometric analysis of soft tissues presented by Arnett, and compare them with the values previously established for the Caucasian population. In this study 200 photographs were analyzed, and the profiles were classified in balanced and unbalanced according to the criteria of a group of specialists. Subsequently, teleradiographs corresponding to the classified profiles were analyzed, with the cephalometric analysis of soft tissues. The values of the different variables were analyzed separately by sex, skeletal class and facial biotype, and the differences between the variables presented by Arnett et al., and those obtained in the present study. For this purpose, statistical significance tests such as the t test and other non- parametric tests were used. There were only significant differences in two variables: inferior lip variables in both sexes, and a greater prominence of the cheekbone in Chilean women, therefore we consider that the values of harmony of Arnett, can also be applied as an aesthetic parameter for the Chilean population.

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